Best instrument/way to program drums from samples?

You most straight forward option is to use Session Drummer
 
Simply load your audio files onto the relevant kit pieces and you can play them like drums (and obviously programme them in the PRV etc.)
 
You can then set Session Drummer to output each drum to a separate track so you can mix and process them individually in Sonar (there are plenty of tutorials on how to do this - try CAKE TV on YouTube)
 
A more "complex" 3rd Party option would be to use a VST like NI BATTERY, which has more control of the sample but I think you will be fine with Session Drummer
 
Good luck and let us know how you get on
 
 

I dabble in hip-hop and edm. There is no apples to apples equivalent to the fl studio drums workflow so it will take some adjusting. The key to making that adjustment is to mentally breakdown the semantic construction of how fl studio works. The simplified version is fl studio's default channel is a single sample sampler set to be triggered via stepsequencer with a default note of C1 ( dont have fl in front of me so default maybe c3 but idea is the same). Options exist to change pitch and even switch to piano roll. Creating a similar setup in Sonar is not as efficient but may offer more overall options in the big picture. Too literally try to emulate flb studio workflow one could simply create an instance of dropzone for every drum sample and use step sequencer for each channel. I honestly would not go that route but it is a possibility.

Two solutions I have actually used are third party drum software and Session drummer. I use Geist because it combines step sequencer, sampler and slicer but there are other options. Session drummer takes a little more prep but can be very effective. For starters it contains quality 808 samples which are still the most commonly used in hip-hop. The awkwardness begins when you wish to use your own samples. Even then it isn only awkward if you need to use multisamples. Otherwise simply replace kit samples with your own. I suggest setting up a template with your most commonly used sounds loaded into SD3.

SFZ Player (included in SONAR) is pretty good. I define my own SFZ layouts in text files.
Documentation here: Sound On Sound article

sharke
Geist is well worth buying, snap it up if you see it in a sale. It's perfect for creating drum kits from samples. There are 8 "engines" each of which can host a kit consisting of 16 pads, and each of those pads can host multiple layers of samples.

For the OP's benefit, the lack of drag 'n' drop velocity layering is the main shortcoming of Session Drummer by comparison. You can only drop one sample on each pad, and Session Drummer just scales the amplitude with velocity. In order to implement velocity-switched layers, you have to build a custom SFZ file for the kit. If Geist let's you drag 'n' drop, multi-samples that would be great. Sounds like a cool plugin in any case.

With geists layers you have the options of having up to 8 layers play round robin, stacked, or based on velocity. Geist does have its cons but it's as close to MPC style production as you will get via software.

The effects are good too. Breverb is built in. In fact the onboard effects are good enough that I can do my whole drum mix in geist and just use a stereo instance In Sonar instead of multiple tracks.